Packages have been developed that contain two or more semiconductor dies attached to a substrate and an interconnect bridge that has connectors, such as pads or lands to connect one die to one or more other dies. In one example, the interconnect bridge attaches a general or central processing unit to a graphics processing unit. In another example, the interconnect bridge attaches a central processing unit to memory. This allows the dies to communicate data directly between each other. Otherwise, these dies would send signals outside the package to hub or other device which would then send the data back into the package and to the other die. Other types of dies and connections may also be possible The die in such a package is embedded into the substrate. In one example, such a package is called an Embedded Interconnect Bridge (EmIB) architecture.
A die in such a package has a certain part of its total interconnect area used as a bridge attach region. For certain memory parts, the bridge may attach to about 20% of the C4 (Controlled Collapse Chip Connection) high density area of the memory chip. The high density interconnect area outside of the bridge attach region portion may contain power rails, test ports, etc. This area may use C4 or any of a variety of other connection technologies. The bridge is embedded into the package substrate and unlike silicon interposers, the embedded interconnect bridge die does not have through-silicon vias to enable power connections from outside the package to the bridge. This is in part because of the very thin structure of such a bridge.